Footage has emerged of the "Iraqi Rambo" Abu Azrael carving the flesh from the body of a charred Islamic State (Isis) fighter. Ayyub al-Rubaie, who goes by the nickname Abu Azrael – "Father of Azrael" – burned the man alive and hung his body from an electricity pylon in Baiji, northern Iraq, according to Al-Jazeera.

In the video Azrael, who has been dubbed by the "Iraqi Rambo" because of his muscular physique and "ferocity on the battlefield", stands holding a sword by the blackened corpse of a suspected Isis militant.

According to Al-Jazeera, he says to the camera: "They sent their elite fighters they said, and look at the third one we got. Isis this will be your fate, we will cut you like shawarma."

He then uses the sharpened blade to carve a chunk out of the dead fighter's leg, before smiling at the camera as he swaggers away. A shawarma is a method of preparing meat by hanging it on a vertical spit, grilling it and then shaving off slices like a kebab.

Fury at violent video

The video has been met with a mixed response online, with some people furious that Azrael and the Iraqi militia have sunk to the same lows as Isis by filming gruesome videos. According to the Daily Mail, Ali Khedery, chief executive of risk management firm Dragoman Partners, wrote: "War crimes are never justifiable. Horrific video featuring a war crime by Iraq's Abu Azrael."

Other people on the internet saw the footage as an act of revenge for the burning of the captured Jordanian pilot Moaz al-Kasasbeh in January 2015.

Azrael defended his actions after the video, entitled "Sunni burned and sliced with sword", spread online and the hashtag trended on Twitter.

"Would I burn a Sunni man?," he asked in a video response, according to Al-Jazeera. "These [fighters] were from the Caucasus. One of them was Asian."

Celebrity militia

The Angel of Death

Abu Azrael's name refers to "Azrael": the angel of death from Jewish and Sikh lore. Although the creature is never actually named in the Koran, some Muslim texts and traditions also use the name to refer to an archangel who escorts the souls of the dead to Allah.

Azrael has become an internet sensation with a Facebook page dedicated to the commander having been "liked" more than 130,000 times. He was a former militia member in Muqtada al-Sadr's Mahdi Army, which led the ferocious Shia response to the 2003 US-led invasion of Iraq, according to Agence France-Presse.

Abu Azrael leads the Imam Ali Brigades, which are part of the Popular Mobilisation Forces, a coalition of Iraqi Shia militias sponsored and armed by the Iraqi government. The mainly Shia Popular Mobilisation Forces have been accused of severe human rights violations and revenge attacks in areas recaptured from Isis. Critics have claimed that the sectarian nature of the Shia militia resembles that of IS's structure.